Include machine info in '#' status reply and add get_machine_info utility

[jamesoncollins]

Motivation

• Provide more useful diagnostics from the # status handler by including machine details (hostname, OS, Python version, CPU, memory, disk, load) alongside uptime and git metadata.
• Make the command handler resilient to the raw_message being either a JSON string or already-parsed dict so tests and the installed SignalBot behavior both work.

Description

• Update run.py to accept c.message.raw_message when it's already a dict and otherwise json.loads it, and to send a combined status_message containing uptime, get_git_info() and get_machine_info() for the # command (uses status_message variable and calls get_machine_info() in the handler).
• Add get_machine_info() and helpers (_format_bytes, _get_memory_info) to utils/misc_utils.py, and import platform, shutil, and socket to report hostname, OS, Python version, processor, CPU count, load average, memory usage and disk usage.
• Update tests/test_run.py to assert the # response contains machine information fields such as Machine:, Hostname:, and OS:.

Testing

• Ran the focused tests with python -m unittest discover -s tests -p "test_run.py" and they passed.
• Verified module syntax by compiling with python -m py_compile run.py utils/misc_utils.py tests/test_run.py, and it succeeded, and directly invoked get_machine_info() to confirm it returns Machine:, Hostname:, OS:, and Python: lines.
• Ran the full test suite with python -m unittest discover -s tests -p "test_*.py", which produced failures unrelated to these changes due to network/proxy restrictions and missing external credentials/API access (external downloads and API calls failed), so those failures are environmental rather than caused by this PR.

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Codex Task